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In contrast to
the typical use of traditional
"personal" computers, in Linux/Unix environments, working "on
the network" has always been the norm, which explains the powerful networking
features of Unix and Linux operating systems. You can easily connect to other
computers and run graphical user interfaces over the network. In this article
we describe a simple method to do your work on any computer on the network without
leaving your seat.

The key command
is: xhost - the server access control program for X. The xhost program is
used to add and delete host (computer) names or user names to the list of machines
and users that are allowed to make connections to the X server. This provides
a rudimentary form of privacy control and security.

Overview:
Let's call the computer you are sitting at the "local host" and the
computer you want to connect to the "remote host". You first use xhost
to specify which computer(s) you want to give permission to connect to (the
X-server of) the local host. Then you connect to the remote host using telnet.
Next you set the DISPLAY variable on the remote host. You want to set this DISPLAY
variable to the local host. Now when you start up a program on the remote host,
its GUI will show up on the local host (not on the remote host).

Example
of a Typical Use

Assume the IP address
of the local host is 128.100.2.16 and the IP address of the remote host is 17.200.10.5.
Depending on the network you are on, you may also be able to use the computer
names (domain names) instead of the IP addresses.

Step 1. On the
local host

Type the following
at the command line:

% xhost +
17.200.10.5<
press return >

Step 2. Log
on to the remote host

% telnet 17.200.10.5

Step 3. On the
remote host (through the telnet connection)

Instruct the remote
host to display windows on the local host by typing:

% setenv DISPLAY
128.100.2.16:0.0

at the command
line. (Instead of setenv you may have to use export on certain shells.)

< press return
>

Step 4. Now
you can run software from the remote host.

E.g.: when you
type % xterm on the remote host, you should see an xterm window on the
local host.

Step 5. After
You Finish

You should remove
the remote host from your access control list as follows. On the local host
type:

% xhost -
17.200.10.5
< press return >

Quick
Reference - xhost

xhost
+ hostname: Adds hostname to X server access control list.

xhost
- hostname: Removes hostname from X server access control list.

xhost
+: Turns off acccess control (all remote hosts will have access to
X server)

xhost
- : Turns access control back on.

Important:
Use the man command (% man) to see how a command is used on your
particular computer.